TRIM21 knockdown facilitates JEV-mediated IRF3 activation and upregulation of the IFN-β level. (A) Cells were either transfected with negative control RNA (NC) or transfected with 10nM siRNA against TRIM21 for 48 h. Cell lysates were resolved on SDS-PAGE and probed with anti-TRIM21 antibody and anti-β-tubulin antibody by Western blotting. A representative image is shown. (B) Cells were either non-transfected (C), transfected with negative control RNA (NC) or with TRIM21 siRNA for 24 h followed by JEV infection for 24 h. Cell lysates were resolved on SDS-PAGE and probed with anti-p-IRF3 antibody, anti-IRF3 and anti-β-tubulin antibodies (loading control) by Western blotting. A representative of three independent experiments is shown. Densitometry analyses of Western blot experiments were performed with normalizing p-IRF-3 and p-IRF-3 against β-tubulin. (C) Real-time PCR for IFN-β1 for siRNA-transfected and JEV-infected cells along with the respective controls was performed and averaged for three independent sets of experiments. (D) Luciferase assay for IFN-β for cells transfected with siRNA against TRIM21 and infected with JEV along with respective controls was performed. Luciferase activity normalized against β-gal activity was averaged and plotted (**p < 0.01, ***p < 0.001 from control).